Known from EP 0 825 081 B1 which is incorporated herein is a motor vehicle having a driving stability function (ESP) and a hydraulic pressure generator in the form of a pump having an electromechanical adjusting unit for an actuator, a transfer between actuating devices and actuating modes being defined on the basis of a minimum application force. This necessarily implies that the electromechanical adjusting unit can generate at least the magnitude of the application force introduced hydraulically by the pump, so that the above-mentioned transfer condition can be fulfilled.
A hydraulic vehicle brake with an electrically actuatable parking brake device is further known from DE 101 50 803 B4 which is incorporated herein. It is proposed in that document that, in order to optimize the stress on the components of the vehicle brake, an application force which is reduced in comparison to a maximum application force is made available by the electric motor when sensor information indicates an actuation of a service brake pedal. In other words, the proportion of application force to be generated by the electric motor is reduced by an amount which has been introduced hydraulically by the vehicle driver. This procedure makes possible a reduction of stress on the electric motor during an application phase by reducing the electrical current demand. This results in a power flow of the reaction forces which is split in a state-dependent manner. This is because, during the actuation phase of application—while the hydraulic assistance is being utilized—a reduced reaction force is present in the electromechanical drivetrain. After the hydraulic pressure has been reduced (driver ends pedal actuation), the hydraulic reaction force component is abruptly superimposed additionally on the power flow of the drivetrain of the parking brake system.
Known systems, devices and methods, in combination with so-called integrated brake calipers, suffer from the disadvantage that an electromechanical drive and transmission system of the actuator and, above all, the brake caliper housing and the brake caliper bridge, must in principle be designed to be overdimensioned mechanically, that is, to have considerably higher power capacity than is strictly necessary, in order to be able to reliably withstand alternating stresses in the transfer process.